Abaixo está uma instrução que descreve uma tarefa de geração de SQL, combinada com uma entrada que fornece mais contexto sobre os esquemas de tabela disponíveis. Escreva o código SQL que responda adequadamente à solicitação
 ###Instrução: Quão longo é "Harvest"?
 ###Tabelas: CREATE TABLE round_robin (round_robin_id AUTO_INCREMENT PRIMARY KEY, Team name VARCHAR, Races INT, Won INT, RR1 Pts. INT, RR2 Pts. INT, RR3 Pts. INT, RR4 Pts. VARCHAR, Total Pts. INT, Ranking INT) CREATE TABLE track_listing (track_listing_id AUTO_INCREMENT PRIMARY KEY, Song VARCHAR, Performer VARCHAR, Original artist VARCHAR, Length VARCHAR, Recorded VARCHAR) CREATE TABLE 2012_calendar_year_ratios_of_crime_per_100000_population (2012_calendar_year_ratios_of_crime_per_100000_population_id AUTO_INCREMENT PRIMARY KEY, State VARCHAR, City VARCHAR, Population INT, Violent Crime VARCHAR, Murder and Non-Negligent Manslaughter INT, Forcible Rape VARCHAR, Robbery INT, Aggravated Assault INT, Property Crime VARCHAR, Burglary INT, Larceny-Theft VARCHAR, Motor Vehicle Theft INT) CREATE TABLE season_by_season (season_by_season_id AUTO_INCREMENT PRIMARY KEY, Season VARCHAR, LKF Cup VARCHAR, Regional Competitions VARCHAR, Europe VARCHAR, Head Coach VARCHAR) CREATE TABLE summary (summary_id AUTO_INCREMENT PRIMARY KEY, First game INT, Played INT, Drawn INT, Lost INT, Percentage VARCHAR)  
SELECT Length FROM track_listing WHERE Song = "harvest"